Interruptible-jet control means for producing short blasts of high pressure fluid



y 29, 1969 J. P. LAVALIER 3,457,893

INTERRUPTIBLE-JET CONTROL MEANS FOR PRODUCING SHORT BLASTS OF HIGHPRESSURE FLUID Filed Dec. 29. 1966 INVENTOR JAMES P LAVAL/Ef? UnitedStates Patent 3,457,893 INTERRUPTlBLE-JET CONTROL MEANS FOR PRO- DUCINGSHORT BLASTS OF HIGH PRESSURE FLUID James P. Lavalier, Mahtomedi, Minn.,assignor to Hart- Carter Company, Chicago, Ill, a corporation ofDelaware Filed Dec. 29, 1966, Ser. No. 605,730

- Int. Cl. Gk 9/00 US. Cl. 116137 9 Claims ABSTRACT OF THE DISCLOSURE Anapparatus for intermittently releasing a short duration blast of highpressure fluid, wherein a bleed actuated diaphragm type main valvecontrolling a high pressure line is operated to release the blast offluid by interruption of a fluid jet which normally acts against thediaphragm of a pilot valve to hold closed the outlet of a bleed linefrom the high pressure side of the main valve diaphragm, the duration ofthe high pressure fluid blast being determined by and commensurate withthe time period that the fluid jet is interrupted to cause the pilotvalve to open the bleed line.

Related application The subject of this application is disclosed in thecopending application of Knowlton-J. Caplan, Ser. No. 572,295, filedAug. 15, 1966, for Method of Filtering a Gaseous Medium and MeansTherefor, said copending application being owned by the assignee of thepresent invention.

Background of the invention This invention pertains to that field of artwhich concerns the intermittent production ofvery short duration blastsor jets of high pressure fluid, the blasts being discharged, atpredetermined intervals and each blast having a duration of a fractionof a second.

Prior means for this purpose involve the use of mechanically actuatedpilot valves for operating a main valve controlling a high pressureline, as by means of cams or stops, or the use of complicated diaphragmand spring arrangements whereby a main valve is momentarily opened. atpredetermined intervals determined by the rate of fluid flow through arestricted passage. In all such prior apparatus or devices the durationof the high pressure discharge was difficult to regulate and in mostinstances could not be reduced to the desired amount for a shockr typeeflect. Also the prior devices often developed considerable and costlymaintenance problems.

By 'the present invention the apparatus required is greatly simplified,moving parts are minimized, and positive and accurate control of highpressure blasts of substantially any desired duration is readilyobtained.

A particularl use for the present invention resides in the controllingof a high pressure, high volume, pneumatic system by means of arelatively low pressure, lowconsumption, interruptible air jet for thecreation of a single sonic velocity shock wave in each of successivehollow gaseous medium filter cells as an aid to the conventionalflushing or back-washing operation.

Summary of the invention The inventive concept involved in thisinvention is to cause extremely rapid operation of a bleed controlleddiaphragm valve for releasing periodic explosiv burst-s of a highpressure fluid by means of a pilot valve, in the bleed line, actuated byan interruptible jet of a relatively low pressure fluid. This isaccomplished by means of a 3,457,893 Patented July 29, 1969 ice pilotvalve of the diaphragm typ which normally holds closed the bleed linefrom the high pressure valve when the pilot diaphragm is pressured by ajet of the low pressure fluid. Interruption of the jet, as by thepassage of a solid element across the jet stream, releases the holdingpressure on the pilot valve diaphragm and, for the duration of the jetinterruption, opens the bleed line to cause automatic opening of themain valve to pass high pressure fluid for the same time period.

The main object of the invention is to cause opening of the main valve,for very short periods and at regular intervals, to release successiveexplosive bursts of high pressure fluid which burst-s are of a constantfraction-of-asecond duration. According to the invention the periodicityand the duration of the bursts of high pressure fluid from the mainvalve are controlled by means of a continuous series of spaced, narrowinterrupters traversing the controlling jet stream at a predeterminedrate, the speed of relative movement between the interrupters and thecontrolling jet stream and the width of the interrupters impacted by thejet stream determining the duration of the respective bursts of highpressure fluid.

Description of the drawings A preferred embodiment of this invention isillustrated in the accompanying drawings in which:

FIG. 1 is a diagrammatic sectional View, showing the nature andoperational relationship of the principal components comprising theimproved control means, the valves being in the closed positionresulting from action of the control jet on the pilot valve.

FIG. 2 is a similar view but showing the elements in the state resultingfrom an interruption of the control jet; and

FIG. 3 is a partly sectioned elevational view, showing the pilot valveand the interruptible jet elements as applied to the rotating member ofa continuous gaseous medium filter of the kind wherein a shock wave isgenerated in each of successive hollow filter elements by the timedrelease of an explosive burst of high pressure gas thereinto.

The preferred embodiment As shown in FIGS. 1 and 2, my improvedsystemfor creating short duration for explosiveblasts'of high pressure fluidcomprises a mainvcontrol valve 10 connected to-a high pressurecompressed air line 12 leading from a surge tank 14 having communicationwith a suitable source of supply, not shown. The outlet 16 of the mainvalve 10 leads directly to a shock wave generator 18 which has a blastdischarge orifice 20 in its side wall.

The main valve 10 shown is of the diaphragmtype wherein the diaphragm 22serves to open and close the outlet 16 as well as the inlet 17 of thevalve in response to pressure changes in the chamber 24 on thehighpressure side of the diaphragm. As shown, the valve chamber 24communicates directly with the compressed .air. line 12 by way of aby-pass passage 26 and opens into a bleed line 28 which terminatesoutwardly in a pilot valve 30.

It will be understood that the main control valve 10 may be of anysuitable pilot operated kind capable of rapid release and stopping of ahigh pressure gas.,flow. One valve suitable. for this purpose is theASCO- No. 83533 pilot operated valve madeby the Automatic SwitchCompany. v

The pilot valve 30, as shown, comprises a hollow body housing adiaphragm32 which divides the body into separate sections 34 and 36. Thesection 34 is the receiver for the control jet and opens from arelativelynarrow receiver passage 38 into which the control jet isnormally directed, as will be described hereinafter. The body section 36is the bleed chamber into which the bleed line 28 terminates through anozzle 40 disposed in axial alignment with a plunger-valve member 42mounted centrally on the diaphragm 32 and normally in axial abutmentwith the nozzle 40 to close the same. As shown, the plungervalve memberis supported for axial sliding movement by an internal brace means 44disposed in the bleed chamber behind the diaphragm 32. Also, the bleedchamber is open to atmosphere through body openings 46.

The control jet is delivered into the receiver passage 38 by means of anaxially aligned nozzle 48 mounted in a suitable air pressure suply means50, the nozzle 48 being spaced from the inlet end of the receiverpassage 38 to permit passage therebetween of an interrupter element 52.

It will now be seen that as long as the air flow across the ambient gap54 (the space between the nozzle 48 and the receiver passage 38) isundisturbed the jet stream 56 from the nozzle 48 transmits a velocitypressure to the low pressure side of the diaphragm 32. Since thispressure is acting over a large area, the plunger 42 of relatively muchsmaller area is forced against the bleed outlet seat 40. As a result thebleed line 28 is closed even though the static pressure therein issubstantially the same as the line pressure of the conduit 12. The highpressure in the main valve pressure chamber 24, supplied by the by-pass26, thus holds the main valve control diaphragm 22 in closed positionagainst the valve outlet 16 leading to the shock wave generator 18, andagainst the inlet 17, as shown in FIG. 1.

When an interference element or interrupter 52 intercepts or passesthrough the jet stream 56 in the ambient gap 54, as shown in FIG. 2, thenormal pressure transmitted into the receiver 34 is blocked, momentarilyrelieving the holding force on the low pressure side of the diaphragm32, and permitting the plunger 42 to be unseated by the pressure in thebleed line 28 leading from the main control valve pressure chamber 24.This allows the pressure in the chamber 24 to be relieved to atmospherethrough the openings 46 of the pilot valve 30, and the diaphragm 22 issuddenly fiexed (for a fraction of a second) to open communicationbetween the ports 16 and 17 and allow the sudden passage of highpressure air from the line 12, under the impetus of the large volume ofthe surge tank 14, into the line 18. This sudden and explosive momentarydischarge of high pressure gas through the orifice 20 creates a singlepressure wave which travels at, or close to, sonic speed away from theorifice 20 in the axial direction thereof. When the interrupter 52 isremoved these operations are reversed and the jet force 56 seats theplunger 42 on the bleed outlet 40, causing the high pressure from theline 12, through the by-pass 26, to reseat the diaphragm 22 and cut offthe pressure flow from the valve through the outlet 16, the partsreturning to the condition of FIG. 1.

This operation of the control system is extremely rapid and the openingand closing movement of the diaphragm 22 occurs between the entry of theinterrupter 52 into the jet stream 56 and the exit of the interruptertherefrom. Thus the duration of high pressure gas flow from the valve 10into the conduit 18 is determined by the size of the interrupter elementand its speed of movement across the jet stream.

In the preferred embodiment of this control system as a shock wavegenerator the nozzle 48 is 0.030 inch in diameter; the gas pressure atthe jet nozzle 48 is about 10 to p.s.i.g.; the ambient gap 54 is 0.375inch; and the receiver 38 has an inside diameter of about 0.100 inch.The interrupter 52 is a rod or peg having a diameter of 0.0315 inch, andthe interrupter crosses the jet stream 56 at a speed of substantially28% inches per minute. With this relationship of the components of thecontrol means and speed of relative movement of the jet streaminterrupter, the on time of the high pressure blast discharge of themain control valve is 0.150 second.

An exemplary arrangement of the pilot valve and interruptible jet meansis shown in FIG. 3 wherein the control means is mounted on the rotatablehollow trunk 60 of a gaseous medium filter such as that described in thebefore-mentioned'copending application of Knowlton J. Caplan, Ser. No.572,295.

As shown in FIG. 3, the jet air supply means 50 connects with acompressed air supply line 62 through a passage 64 in the trunk body.This air is discharged as a jet from the nozzle 48, across the ambientgap 54, into the receiver inlet 38 0f the pilot valve 30. With thisarrangement the pilot valve and jet nozzle travel together, angularly,as the trunk 60 rotates and the pilot is intended to operates to cause apredetermined number of blasts of high pressure air during each completerevolution of the trunk 60. Thus there must be an interrupter for eachhigh pressure blast to occur in one revolution of the trunk 60 and theseinterrupters must be stationary and angularly spaced in the path of thetraveling jet-pilot elements to correspond with the angular location ofeach blast delivery.

As shown in FIG. 3, the ambient gap 54 opens downwardly to straddle thevertical rim of a cup-like member 66. The several interrupters 52, heresmall diameter rods, are mounted on the rim of the member 66, inappropriate angularly-spaced relation, and extend upwardly a distancesufficient to cross the-jet stream. Thus, as the trunk 60 rotates, thejet stream flow into the receiver 38 is intercepted momentarily as itpasses each interrupter 52 and the pilot valve 30 is operated to performits function of causing the release of a short duration blast of highpressure air.

Major advantages of my improved control system reside in the substantialelimination of moving parts, minimum maintenance requirements, and thefact that it is practically insensitive to environmental conditions.

Although but one specific embodiment of this invention have beenhereinshown and described, it will be understood that details of thestructures involved may be altered or omitted without departing from thespirit of the invention as defined by the following claims.

I claim:

1. Apparatus for producing short duration blasts of a high pressurefluid from the discharge outlet of a bleed controlled main valveconnected with a high pressure supply line by means of a pilot valve foropening and closing a bleed passage leading from the high pressure sideof said main valve and terminating in an outlet orifice. wherein theimprovement comprises a pilot valve into which said bleed passageterminates and which has a diaphragm operable to open and close the saidoutlet orifice, means for directing pressure from a fluid-jet streamagainst the side of the pilot valve diaphragm opposite the side adjacentthe said outlet orifice for closing the same, and means for interruptingsaid fluid-jet stream for predetermined short periods of time.

2. Apparatus according to claim 1 wherein the pilot valve comprises areceiver section and a bleed section separated and sealed from eachother by the diaphragm, each of said sections having an opening toambient atmosphere and the fluid-jet stream being directed into theopening of the receiver section from a nozzle spaced therefrom.

3. Apparatus according to claim 2 wherein the bleed line outletcomprises a nozzle from which the outlet orifice is directed toward saiddiaphragm.

4. Apparatus according to claim 2 wherein a valve member in said bleedsection is axially aligned with the bleed line outlet orifice and isheld seated against the orifice by the diaphragm when the diaphragm isacted upon by the pressure of said fluid-jet stream.

5. Apparatus according to claim 3 wherein a plungervalve member in saidbleed section is axially aligned with the orifice of said bleed linenozzle and is held seated against said nozzle by said diaphragm to closesaid orifice when the receiver section is under the pressure of saidfluid-jet stream.

6. An apparatus according to claim 1 wherein the means for interruptingthe fluid-jet stream comprises a rod disposed normal to the said jetstream and laterally traversing the jet-stream at a predetermined speed.

7. An apparatus defined by claim 2 wherein the means for interruptingthe fluid-jet stream comprises a rod disposed normal to the said jetstream and laterally traversing the jet-stream through the space betweenthe jet nodzle and the opening of the receiver section at apredetermined speed.

8. A shock wave generating means comprising an apparatus according toclaim 1 and wherein the burst f high pressure fiuid from the main valveis discharged into a hollow elongate body closed at one end and havingits other end connected to the discharge outlet of the said main valve,the said elongate body having a shockwave producing blast-dischargeorifice in its side wall.

9. A shock wave generating means comprising an apparatus according toclaim 6 and wherein a hollow elongated cylindrical body closed at itsdistal end is connected to the discharge outlet of the main valve and isprovided 'with an orifice in its side wall intermediate its ends forproducing a single shock-wave by the issue of a blast of high pressurefluid therefrom.

References Cited UNITED STATES PATENTS 2,065,702 12/1936 Hubbard.2,526,972 10/ 1950 Ray 25l45 XR 3,216,252 11/1965 Chapman et a1. 73-2293,258,023 6/1966 Bowles 13781.5

FOREIGN PATENTS 1,021,560 3/1966 Great Britain.

LOUIS J. CAPOZI, Primary Examiner US. Cl. X.R.

